My Biology: Tugas Fisika Dasar

CHAPTER I

PREFACE

1.1.Background

In this modern era technology becomes important. Technology can facilitate the work and shorten the actual distance of thousands of miles, for example by using the telephone. One important thing that supports the existence of technology is a means, such as media or wave energy.

Many electronic items that utilize the properties of waves, such as the nature of the wave can propagate in a vacuum used by humans to make the light bulb in the Bolam where space is a vacuum.

Many electronic devices around us who utilize the technology wave, but most of us do not fully know and understand. And we will discuss the use of sound waves and waves in everyday life more specifically in next chapter.

1.2.Problem of Study

1. What is the mean of wave?

2. What else are the kind of wave?

3. How the properties of waves?

4. How the use of waves in everyday life?

1.3.Purpose

1. To know the wave is.

2. To find all kinds of waves.

3. To know the properties of waves.

4. Capable to examine the use of waves in everyday life.

CHAPTER II

DISCUSSION

2.1. Definition

The waves are vibrations that propagate, either through or not through the medium. There is a wave propagation requires a medium, such as a wave through the umbilical cord and some that do not require a medium, which means that the waves can propagate through a vacuum (no-air), such as electrical magnetic waves can propagate in a vacuum. Wave propagation in the medium is not followed by the propagation medium, but the medium particles will vibrate. Mathematical formulation of the wave propagation can be derived by observation of a pulse. Judging from the provisions of the repetition of shapes, waves divided into periodic and non-periodic waves.

Based on the vibration source, without the intermediary medium, the waves can be classified into two categories, namely mechanical waves and electromagnetic waves. Wave mechanics is something that can be formed and propagated in an elastic material intermediate substance. As a specific example is the sound wave in gases, in liquids and in solids. Electromagnetic wave is propagation in transversely between the electric field and magnetic field in any direction.

Wave is defined as the energy vibrations that propagate. In everyday life many people think that the wave is propagating in the resonance or particle, it is slightly incorrect because the wave is propagating in the energy that belongs to the vibrateion. In fact the flow of water in a vast ocean. According to the flow of sea water was not caused by a wave but rather is caused by temperature differences in ocean water. But it may also affect displacement medium particles, when a wave through a medium gas substance that bonds between the particles is very weak then it is possible to move the position of the air particles due to exposure to wave energy. It is said that the medium particles involved move although the particle displacement is not as much.

2.2. The Sort of Wave

In general, there are only two types of waves, namely, mechanical waves and electromagnetic waves. Type of wave based on the wave propagation medium is:

a. Mechanical wave is a wave propagation requires a medium in which the energies for the purpose of propagation of a wave process. Sound is an example of a mechanical wave that propagates through air pressure changes in a (tight- air molecules).

b. Electromagnetic waves, the waves can propagate even though there is no medium. Energy electromagnetic waves propagating in a few characters that can be measured, namely wave length, frequency, amplitude, and speed. Examples electromagnetic waves in everyday life are as follows:

1. Radio waves.

2. Micro waves.

3. Infrared ray.

4. Ultraviolet light.

5. Visible light.

6. X-rays and.

7. Gamma ray.

While based on the direction of propagation and vibration, is divided into two, namely transverse and longitudinal waves.

a. Transverse waves, the waves knock the direction perpendicular to the direction of vibration. Examples of transverse waves are waves of rope. When we move the rope up and down, it appears that the rope moves up and down in a direction perpendicular to the direction of wave motion. The highest point is called the wave peak, while the lowest point is called the valley. Amplitude is the maximum height or maximum depth of the valley, measured from the equilibrium position. The distance of two points in succession on the same wave is called wavelength (called lambda - the Greek letter). Wavelengths can also be considered as the distance from peak to peak or from valley to valley distance.

b. Longitudinal waves, i.e. waves that knock direction parallel to the direction of vibration (e.g. wave slinky). Waves occur on a vibrated slinky, direction strech slinky form density and strain. Distance of two densities adjacent to two adjacent strains is called a wave.

Physical properties of waves include:

1. Wave reflection, deflection direction of wave propagation is due to the different medium strech limit. Reflected wave has the opposite direction to the wave coming but mesh is on the same medium.

2. Wave refraction, is the deflection direction of wave propagation from the deep into shallow areas. In the event of refraction of the wave frequency is always fixed, but propagation wavelength and fast changing.

3. Wave polarization, is the change in direction of propagation of the wave after passing through the medium of Polaroid. Polarization can only happen in transverse waves. No-polarization light is a vibration of pure light in all directions. Light having linear polarization when light passes through a Polaroid because the direction of propagation is always the same.

4. Wave dispersion, is the change in the wave form when waves propagate through a medium. Examples of the disintegration of the white light wave are (polychromatic) into the colors of the rainbow as through a glass prism. Waves that can retain its shape in non dispersion medium is called wave no-disperse. Examples no-disperse medium is air.

5. Wave diffraction, is spread when the direction of wave propagation through a narrow slit. When the waves into a narrow slit, each point on the slit acts as a source of new wave with the radial direction of propagation.

6. Wave interference, is the influence of waves generated by the superposition results. If the two waves that combined have the same phase, it will produce a mutually reinforcing wave (constructive interference). If the combined wave has the opposite phase, it will produce a mutually debilitating wave (destructive interference).

Based on the propagation medium, the wave propagation can be classified based on the dimensions and direction of harassment.

1. Wave 1 dimensions, ie waves that propagate in one direction. (eg waves straps).

2. 2-dimensional wave is a wave that propagates in the form field. (eg water waves).

3. 3-dimensional waves are waves that propagate in space. Propagate in all directions. (Examples of radio waves, micro, light).

Sound Waves

The sound is not always able to be heard by the human ear. The sound of the bat sounds to communicate, for example, it was not able captured by the human ear because the frequency is very large. The sound of a plucked guitar string in Jakarta can not be captured by the people in Bandung, because the distance is too far though the frequency corresponding to the frequency of the human ear to hear. In addition, the sound of the human eye blink nor can we hear because the energy is too small. Therefore, there are several requirements that the sound can be heard by the human ear, that is:

1. It has a natural frequency corresponding threshold of human hearing

2. Located at a distance that can be heard.

3. Have enough energy to get to the human eardrum.

Now, we will limit our discussion only to the sound audible to the human ear. At the sound wave is a longitudinal wave, the sound propagates in a direction parallel to the vibration of the medium. Generally, symptoms sound waves more often we observe in the medium of air, because it is more easily observed.

As we discussed above concerning the nature / characteristics of a sound wave, it turns out the sound is produced by vibrating objects disorders, especially musical instruments, such as guitar, flute, etc.. And what about the human voice? Does that include sound waves? Apparently, too, including the human voice sound waves, which arise due to vibration in the human vocal cords, and propagates through the medium of sound sehinggan air can be up to our ears.

Including longitudinal sound waves because the area around the sound propagation is experiencing density and renggangan. An example is the phenomenon of vibration in the tuning fork. Tuning fork tooth movement in and out causing the surrounding air pressure difference. Low pressure areas around the sound source that we are familiar with renggangan, and high-pressure area is that we know the density.

We can recognize the sound waves through the symptoms it creates, such as resonance, pelayangan, and the Doppler effect.

- Resonance

All objects when it vibrates / vibrated bound to cause sound, although sometimes the sound is not heard clearly on objects that vibrate with small intensity. Therefore, every object has a natural frequency of each, which is a set of frequencies that occur when an object vibrates.

If there is an object vibrating objects and connect with others who have the same natural frequency, then it will force both participate vibrating objects. Like when we vibrate a tuning fork, then another nearby tuning fork will also vibrate. This is what we are familiar with resonance. Resonance events are common in some parts of musical instruments, such as strings and organ pipes.

· Pipe Organa (open and closed).

Pipe organ is an instrument that uses air as the source of the sound field. Several tools have such principles which this organ pipe flute, saxophone, etc. There are two types of pipe organ, the organ pipes open and closed organ pipes.

In an open organ pipe, the pipe organ has always formed the abdomen. Image patterns of transverse waves in an open organ pipe are:

The equation to determine the frequency of a particular tone of an open organ pipe is:

In a closed organ pipe, closed end of the pipe that always happens knot. Image patterns of transverse waves in the pipe organ covered include:

Pattern comparison frequency in a closed organ pipe is fo: f1: f2: ... is 1: 3: 5: ... The equation to determine the frequency of a particular tone in the pipeline are:

· Doppler Effect

As we stood on the curb and watched the passing vehicles, we can hear the difference in sound from the vehicle when approaching and moving away from us. When the vehicle approached, we heard a noise louder than when the vehicle is being away / away from us. This phenomenon is called the Doppler effect.

The Doppler effect is a phenomenon difference frequency heard by an observer from a source of sound due to the relative velocity between the observer to the source. That's why we can hear a louder vehicle when the vehicle is moving toward us. The magnitude of the audible frequency changes depending on the relative motion, formulated as follows:

Positive or negative sign is determined by the following conditions:

- Vp positif apabila pengamat bergerak mendekati sumber, dan negatif apabila pengamat bergerak menjauhi sumber.

- Vs positif apabila sumber bergerak menjauhi pengamat, dan negatif apabila sumber bergerak mendekati pengamat.

Wave of Light

· Wave Nature of Light

Light is a transverse wave that includes electromagnetic waves. Light can propagate in a vacuum at a speed of 3 x 108 m / s.

The properties of light:

1. May experience reflection (reflection)

2. Can undergo refraction (refraction)

3. May experience stretching (diffraction)

4. Can be added (interference)

5. Can be described (dispersion)

6. Can be absorbed vibration direction (polarization)

7. As wave and particle nature

· Light intensity

The amount of radiant energy emitted as light in a particular direction is called the light intensity and is expressed with units of candela (cd) with the symbol I.

2.3. Application examples Waves and Sound Waves in Everyday Life:

1. Radio

Radio energy is a form of electromagnetic energy level of the lowest, with a range of wavelengths from thousands of kilometers to less than one meter. Using the most is communication, to examine space and radar systems. Radar is useful for studying weather patterns, storms, create a 3D map of the earth surface, measure rainfall, the movement of ice in the Polar Regions and monitor the environment. A wavelength is ranging from 0.8 - 100 cm.

2. Microwave

The wavelength of microwave radiation ranges from 0.3 - 300 cm. Its use is mainly in the field of communication and information delivery through open spaces, cooking, and PJ active systems. In the PJ system active microwave pulse is fired through a target and its reflection was measured to study the characteristics of the target. As an application example is Tropical Rainfall Measuring Mission's (TRMM) Microwave Imager (TMI), which measures the microwave radiation emitted from the electromagnetic spectrum electromagnetic energy of Earth's atmosphere to measure evaporation, water content in the cloud and rain intensity.

3. Infrared

Health conditions can be diagnosed by examining the infrared emissions from the body. Photo special called infrared thermo gram is used to detect blood circulation problems, arthritis and cancer. Infrared radiation can also be used in burglar alarms. A thief without his knowledge would block light and hide alarm. The remote control communicates with the TV via infrared radiation generated by the LED (Light Emitting Diode) contained in the unit, so that we can remotely turn on the TV using the remote control.

4. Ultraviolet

UV light is needed in the assimilation of plants and can kill germs in the skin.

5. X-ray

X-rays are commonly used in the medical field position to photograph the bones in the body especially for determining the fracture. However, the uses of X-rays have to be careful because the network of human cells can be damaged by the use of X-rays that are too long.

6. Musical instrument

In musical instruments like guitar sound sources produced by vibrating objects, namely strings. If the strings are plucked by amplitude (deviation) is large then the sound will be louder generated. And if tension strings stretched curve the sound will be higher similarly drums and other musical instruments. The sound arises because the source of the sound vibrated.

7. Blind glasses, equipped with ultrasonic transmitter and receiver utilizing ultrasonic transmission and reception. Notice the blind glass in the picture below.

8. Measure the depth of the sea, to determine the depths of the sea (d) if known propagation speed of sound (v) and time interval (t), sending and receiving pulses are:

9. Medical devices, such as the USG (Ultra Sound Graph). For example, ultrasonic scanning is done by dragging the movement of the probe around the abdominal skin of pregnant mothers would show a picture of a fetus on the screen. By observing the fetal images, doctors can monitor the growth, development and health of the fetus. Unlike X-ray examination, ultrasound is safe (no risk), both the mother and fetus for examination or testing with ultrasonic does not damage the material that is passed, then it is called ultrasonic testing is non-destructive testing (non-destructive testing, NDT abbreviated). Ultrasonic scanning technique is also used to check the liver (liver cancer indication is there or not) and the brain. Making the ultrasound is to remove damaged brain tissue without having to perform brain surgery. In this way, the patient does not need to undergo a risky brain surgery. Removal of damaged brain tissue can be done without having to cut and sew up hole in the scalp or skull.

CHAPTER III

CLOSING

3.1. Conclusion

1. Wave is defined as the energy vibrations that propagate. In everyday life many people think that the wave is propagating in the resonance or particle, it is slightly incorrect because the wave is propagating in the energy that belongs to the vibration.

2. Types of Waves

a. Wave by the medium can be divided into two kinds, as follows:

1. Mechanical waves in the wave propagation require a medium. Examples of mechanical waves are sound waves.

2. Electromagnetic waves are waves that do not require the propagation medium. Examples electromagnetic waves are light waves.

b. Wave in the direction propagation divided into 2 types, namely:

1. Longitudinal waves are waves that propagation direction parallel to the direction of vibration. An example is a sound wave.

2. Transverse wave is a wave whose direction perpendicular propagation with the direction vibration. For example, light waves.

Physical properties of waves include:
1. Wave reflection,
2. Wave refraction,
3. Polarization waves,
4. Wave dispersion,
5. Wave diffraction,
6. wave interference

Application examples Waves and Sound Waves in Everyday Life:
1. Radios
2. Microwave